“Three-in-one”cathode,achieved via B-site heavy-doping of transition elements(typically Co,Fe)into proton-conductive perovskite,holds promise for enhancing the performance of proton-conducting solid oxide fuel cell(...“Three-in-one”cathode,achieved via B-site heavy-doping of transition elements(typically Co,Fe)into proton-conductive perovskite,holds promise for enhancing the performance of proton-conducting solid oxide fuel cell(H-SOFC)operated below 650℃for electricity generation.However,its electrochemical behavior above 650℃,essential for improving the efficiency of H-SOFC for fuel conversion,remains insufficiently explored.It is still challenging to propose guidance for the design of“threein-one”cathode toward optimal H-SOFC performance below and above 650℃,with the prerequisite of gaining a comprehensive understanding of the roles of Co and Fe in determining the H-SOFC performance.This work is to address this challenge.Through theoretical/experimental studies,Co is identified to play a role in improving the oxygen reduction reaction(ORR)activity while Fe plays a role in facilitating the cathode/electrolyte interfacial proton conduction.Therefore,if the operating temperature is above 650℃,lowering the Co/Fe ratio in“three-in-one”cathode becomes crucial since the limiting factor shifts from ORR activity to proton conduction.Implementing this strategy,the SOFC using BaCo_(0.15)-Fe_(0.55)Zr_(0.1)Y_(0.1)Yb_(0.1)O_(3−δ)cathode achieves peak power densities of 1.67Wcm^(−2)under H-SOFC mode at 700℃and 2.32Wcm^(−2)under dual ion-conducting SOFC mode at 750℃,which are the highest reported values so far.展开更多
The development of flame retardant or nonflammable electrolytes is the key to improve the safety of lithium batteries,owing to inflammable organic solvents and polymer matrix in common liquid and polymer electrolytes ...The development of flame retardant or nonflammable electrolytes is the key to improve the safety of lithium batteries,owing to inflammable organic solvents and polymer matrix in common liquid and polymer electrolytes regarded as the main cause of battery fire.Herein,a series of solid-state polyphosphate oligomers(SPPO)as a three-in-one electrolyte that integrated the roles of lithium salt,dissociation matrix,and flame retardant were synthesized.The well-designed SPPO electrolytes showed an optimal ionic conductivity of 5.5×10^(-4)S cm-1at 30℃,an acceptable electrochemical window up to 4.0 V vs.Li/Li+,and lithium ion transference number of 0.547.Stable Li-ion stripping/plating behavior for 500 h of charge-discharge cycles without internal short-circuit in a Li|SPPO|Li cell was confirmed,together with outstanding interface compatibility between the SPPO electrolyte and lithium foil.The optimal Li|SPPO|LiFePO4cell presented good reversible discharge capacity of 149.4 mA h g-1at 0.1 C and Coulombic efficiency of 96.4%after 120 cycles.More importantly,the prepared SPPO cannot be ignited by the lighter fire and show a limited-oxygen-index value as high as 35.5%,indicating splendid nonflammable nature.The SPPO could be a promising candidate as a three-in-one solid-state electrolyte for the improved safety of rechargeable lithium batteries.展开更多
Black phosphorus(BP)nano-materials,especially BP quantum dots(BPQDs),performs outstanding photothermal antitumor effects,excellent biocompatibility and biodegradability.However,there are several challenges to overcome...Black phosphorus(BP)nano-materials,especially BP quantum dots(BPQDs),performs outstanding photothermal antitumor effects,excellent biocompatibility and biodegradability.However,there are several challenges to overcome before offering real benefits,such as poor stability,poor dispersibility as well as difficulty in tailoring other functions.Here,a“three-in-one”mitochondria-targeted BP nano-platform,called as BPQD-PEG-TPP,was designed.In this nano-platform,BPQDs were covalently grafted with a heterobifunctional PEG,in which one end was an aryl diazo group capable of reacting with BPQDs to form a covalent bond and the other end was a mitochondria-targeted triphenylphosphine(TPP)group.In addition to its excellent near-infrared photothermal properties,BPQD-PEG-TPP had much enhanced stability and dispersibility under physiological conditions,efficient mitochondria targeting and promoted ROS production through a photothermal effect.Both in vitro and in vivo experiments demonstrated that BPQD-PEG-TPP performed much superior photothermal cytotoxicity than BPQDs and BPQD-PEG as the mitochondria targeted PTT.Thus this“three-in-one”nanoplatform fabricated through polymer grafting,with excellent stability,dispersibility and negligible side effects,might be a promising strategy for mitochondria-targeted photothermal cancer therapy.展开更多
Using porous carbon hosts in cathodes of Li-S cells can disperse S actives and offset their poor electrical conductivity.However,such reservoirs would in turn absorb excess electrolyte solvents to S-unfilled regions,c...Using porous carbon hosts in cathodes of Li-S cells can disperse S actives and offset their poor electrical conductivity.However,such reservoirs would in turn absorb excess electrolyte solvents to S-unfilled regions,causing the electrolyte overconsumption,specific energy decline,and even safety hazards for battery devices.To build better cathodes,we propose to substitute carbons by In-doped SnO_(2)(ITO)nano ceramics that own three-in-one functionalities:1)using conductive ITO enables minimizing the total carbon content to an extremely low mass ratio(~3%)in cathodes,elevating the electrode tap density and averting the electrolyte overuse;2)polar ITO nanoclusters can serve as robust anchors toward Li polysulfide(LiPS)by electrostatic adsorption or chemical bond interactions;3)they offer catalysis centers for liquid–solid phase conversions of S-based actives.Also,such ceramics are intrinsically nonflammable,preventing S cathodes away from thermal runaway or explosion.These merits entail our configured cathodes with high tap density(1.54 g cm^(−3)),less electrolyte usage,good security for flame retardance,and decent Li-storage behaviors.With lean and LiNO_(3)-free electrolyte,packed full cells exhibit excellent redox kinetics,suppressed LiPS shuttling,and excellent cyclability.This may trigger great research enthusiasm in rational design of low-carbon and safer S cathodes.展开更多
LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) is extensively researched as one of the most widely used commercially materials for Li-ion batteries at present.However,the poor high-voltage performance(≥4.3 V)with low reversible cap...LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) is extensively researched as one of the most widely used commercially materials for Li-ion batteries at present.However,the poor high-voltage performance(≥4.3 V)with low reversible capacity limits its replacement for LiCoO_(2) in high-end digital field.Herein,three-in-one modification,Na-doping and Al_(2)O_(3)@Li_(3)BO_(3) dual-coating simultaneously,is explored for single-crystalline LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)(N-NCM@AB),which exhibits excellent high-voltage performance.N-NCM@AB displays a discharge-specific capacity of 201.8 mAh g^(−1) at 0.2 C with a high upper voltage of 4.6 V and maintains 158.9 mAh g^(−1) discharge capacity at 1 C over 200 cycles with the corresponding capacity retention of 87.8%.Remarkably,the N-NCM@AB||graphite pouch-type full cell retains 81.2% of its initial capacity with high working voltage of 4.4 V over 1600 cycles.More importantly,the fundamental understandings of three-in-one modification on surface morphology,crystal structure,and phase transformation of N-NCM@AB are clearly revealed.The Na+doped into the Li–O slab can enhance the bond energy,stabilize the crystal structure,and facilitate Li+transport.Additionally,the interior surface layer of Li^(+)-ions conductor Li_(3)BO_(3) relieves the charge transfer resistance with surface coating,whereas the outer surface Al_(2)O_(3) coating layer is beneficial for reducing the active materials loss and alleviating the electrode/electrolyte parasite reaction.This three-in-one strategy provides a reference for the further research on the performance attenuation mechanism of NCM,paving a new avenue to boost the high-voltage performance of NCM cathode in Li-ion batteries.展开更多
Ammonia is a key industry raw material for fertilizers and the electro-reduction of N_(2)(NRR)can be served as a promising method.It is urgently needed to discover advanced catalysts while the lack of design principle...Ammonia is a key industry raw material for fertilizers and the electro-reduction of N_(2)(NRR)can be served as a promising method.It is urgently needed to discover advanced catalysts while the lack of design principles still hinders the high-throughput screen of efficient candidates.Herein,we have provided an up-to-date review of NRR catalysts mainly on theoretical works and highlighted the latest achievements on descriptors,which can be served as valid guidance of optimal catalysts.The descriptors are classified with adsorption energy and the corresponding derived ones,which can screen the NRR catalysts from various aspects.Finally,the challenges and opportunities in the descriptor field are presented.展开更多
In today's fast-paced modern life, whether for fitness training, outdoor adventures, or daily commutes, we all yearn for quick-dry apparel that can rapidly wick away moisture and keep our bodies dry and comfortabl...In today's fast-paced modern life, whether for fitness training, outdoor adventures, or daily commutes, we all yearn for quick-dry apparel that can rapidly wick away moisture and keep our bodies dry and comfortable. As a standout in functional textiles, quick-dry fabrics are becoming the top choice for more and more people, thanks to their exceptional moisture-wicking performance and rapid drying capabilities.展开更多
基金supported by the Natural Sciences and Engineering Research Council(NSERC)of Canada,Discovery Grant(GRPIN-2016-05494)Strategic Research Projects of Alberta Innovates Technology Futures(#G2016000655)funding from the Canada First Research Excellence Fund(CFREF-2015-00001).
文摘“Three-in-one”cathode,achieved via B-site heavy-doping of transition elements(typically Co,Fe)into proton-conductive perovskite,holds promise for enhancing the performance of proton-conducting solid oxide fuel cell(H-SOFC)operated below 650℃for electricity generation.However,its electrochemical behavior above 650℃,essential for improving the efficiency of H-SOFC for fuel conversion,remains insufficiently explored.It is still challenging to propose guidance for the design of“threein-one”cathode toward optimal H-SOFC performance below and above 650℃,with the prerequisite of gaining a comprehensive understanding of the roles of Co and Fe in determining the H-SOFC performance.This work is to address this challenge.Through theoretical/experimental studies,Co is identified to play a role in improving the oxygen reduction reaction(ORR)activity while Fe plays a role in facilitating the cathode/electrolyte interfacial proton conduction.Therefore,if the operating temperature is above 650℃,lowering the Co/Fe ratio in“three-in-one”cathode becomes crucial since the limiting factor shifts from ORR activity to proton conduction.Implementing this strategy,the SOFC using BaCo_(0.15)-Fe_(0.55)Zr_(0.1)Y_(0.1)Yb_(0.1)O_(3−δ)cathode achieves peak power densities of 1.67Wcm^(−2)under H-SOFC mode at 700℃and 2.32Wcm^(−2)under dual ion-conducting SOFC mode at 750℃,which are the highest reported values so far.
基金the financial support of the National Natural Science Foundation of China(21961044,22169024)the Yunnan Fundamental Research Projects(202105AC160072,202101BC070001-019,202101AT070280,202102AB080017)the Yunnan University’s Research Innovation Fund for graduate students(2021Y394)。
文摘The development of flame retardant or nonflammable electrolytes is the key to improve the safety of lithium batteries,owing to inflammable organic solvents and polymer matrix in common liquid and polymer electrolytes regarded as the main cause of battery fire.Herein,a series of solid-state polyphosphate oligomers(SPPO)as a three-in-one electrolyte that integrated the roles of lithium salt,dissociation matrix,and flame retardant were synthesized.The well-designed SPPO electrolytes showed an optimal ionic conductivity of 5.5×10^(-4)S cm-1at 30℃,an acceptable electrochemical window up to 4.0 V vs.Li/Li+,and lithium ion transference number of 0.547.Stable Li-ion stripping/plating behavior for 500 h of charge-discharge cycles without internal short-circuit in a Li|SPPO|Li cell was confirmed,together with outstanding interface compatibility between the SPPO electrolyte and lithium foil.The optimal Li|SPPO|LiFePO4cell presented good reversible discharge capacity of 149.4 mA h g-1at 0.1 C and Coulombic efficiency of 96.4%after 120 cycles.More importantly,the prepared SPPO cannot be ignited by the lighter fire and show a limited-oxygen-index value as high as 35.5%,indicating splendid nonflammable nature.The SPPO could be a promising candidate as a three-in-one solid-state electrolyte for the improved safety of rechargeable lithium batteries.
基金We are grateful for the financial support from National Natural Science Foundation of China(51703258,81772449 and 81971081)Guangzhou science technology and innovation commission(201804010309 and 201803010090)Science,Technology&Innovation Commission of Shenzhen Municipality(JCYJ20180307154606793 and JCYJ20180507181654186).
文摘Black phosphorus(BP)nano-materials,especially BP quantum dots(BPQDs),performs outstanding photothermal antitumor effects,excellent biocompatibility and biodegradability.However,there are several challenges to overcome before offering real benefits,such as poor stability,poor dispersibility as well as difficulty in tailoring other functions.Here,a“three-in-one”mitochondria-targeted BP nano-platform,called as BPQD-PEG-TPP,was designed.In this nano-platform,BPQDs were covalently grafted with a heterobifunctional PEG,in which one end was an aryl diazo group capable of reacting with BPQDs to form a covalent bond and the other end was a mitochondria-targeted triphenylphosphine(TPP)group.In addition to its excellent near-infrared photothermal properties,BPQD-PEG-TPP had much enhanced stability and dispersibility under physiological conditions,efficient mitochondria targeting and promoted ROS production through a photothermal effect.Both in vitro and in vivo experiments demonstrated that BPQD-PEG-TPP performed much superior photothermal cytotoxicity than BPQDs and BPQD-PEG as the mitochondria targeted PTT.Thus this“three-in-one”nanoplatform fabricated through polymer grafting,with excellent stability,dispersibility and negligible side effects,might be a promising strategy for mitochondria-targeted photothermal cancer therapy.
基金support by the National Natural Science Foundation of China(51802269,21773138)Fundamental Research Funds for the Central Universities(XDJK2019AA002)+1 种基金the Venture&Innovation Support Program for Chongqing Overseas Returnees(cx2018027)the innovation platform for academicians of Hainan province.
文摘Using porous carbon hosts in cathodes of Li-S cells can disperse S actives and offset their poor electrical conductivity.However,such reservoirs would in turn absorb excess electrolyte solvents to S-unfilled regions,causing the electrolyte overconsumption,specific energy decline,and even safety hazards for battery devices.To build better cathodes,we propose to substitute carbons by In-doped SnO_(2)(ITO)nano ceramics that own three-in-one functionalities:1)using conductive ITO enables minimizing the total carbon content to an extremely low mass ratio(~3%)in cathodes,elevating the electrode tap density and averting the electrolyte overuse;2)polar ITO nanoclusters can serve as robust anchors toward Li polysulfide(LiPS)by electrostatic adsorption or chemical bond interactions;3)they offer catalysis centers for liquid–solid phase conversions of S-based actives.Also,such ceramics are intrinsically nonflammable,preventing S cathodes away from thermal runaway or explosion.These merits entail our configured cathodes with high tap density(1.54 g cm^(−3)),less electrolyte usage,good security for flame retardance,and decent Li-storage behaviors.With lean and LiNO_(3)-free electrolyte,packed full cells exhibit excellent redox kinetics,suppressed LiPS shuttling,and excellent cyclability.This may trigger great research enthusiasm in rational design of low-carbon and safer S cathodes.
基金We gratefully acknowledge the financial support from the National Natural Science Foundation of China(52070194,51902347,51908555,and 51822812)Natural Science Foundation of Hunan Province(2020JJ5741)the Graduate Innovation Project of Central South University(2020zzts093).
文摘LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) is extensively researched as one of the most widely used commercially materials for Li-ion batteries at present.However,the poor high-voltage performance(≥4.3 V)with low reversible capacity limits its replacement for LiCoO_(2) in high-end digital field.Herein,three-in-one modification,Na-doping and Al_(2)O_(3)@Li_(3)BO_(3) dual-coating simultaneously,is explored for single-crystalline LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)(N-NCM@AB),which exhibits excellent high-voltage performance.N-NCM@AB displays a discharge-specific capacity of 201.8 mAh g^(−1) at 0.2 C with a high upper voltage of 4.6 V and maintains 158.9 mAh g^(−1) discharge capacity at 1 C over 200 cycles with the corresponding capacity retention of 87.8%.Remarkably,the N-NCM@AB||graphite pouch-type full cell retains 81.2% of its initial capacity with high working voltage of 4.4 V over 1600 cycles.More importantly,the fundamental understandings of three-in-one modification on surface morphology,crystal structure,and phase transformation of N-NCM@AB are clearly revealed.The Na+doped into the Li–O slab can enhance the bond energy,stabilize the crystal structure,and facilitate Li+transport.Additionally,the interior surface layer of Li^(+)-ions conductor Li_(3)BO_(3) relieves the charge transfer resistance with surface coating,whereas the outer surface Al_(2)O_(3) coating layer is beneficial for reducing the active materials loss and alleviating the electrode/electrolyte parasite reaction.This three-in-one strategy provides a reference for the further research on the performance attenuation mechanism of NCM,paving a new avenue to boost the high-voltage performance of NCM cathode in Li-ion batteries.
基金supported by the National Natural Science Foundation of China(No.21603109)the Henan Joint Fund of the National Natural Science Foundation of China(No.U1404216)+2 种基金the Special Fund of Tianshui Normal University,China(No.CXJ2020-08)the Scientific Research Program Funded by Shaanxi Provincial Education Department(No.20JK0676)supported by Natural Science Basic Research Program of Shanxi(Nos.2022JQ-108,2022JQ-096).
文摘Ammonia is a key industry raw material for fertilizers and the electro-reduction of N_(2)(NRR)can be served as a promising method.It is urgently needed to discover advanced catalysts while the lack of design principles still hinders the high-throughput screen of efficient candidates.Herein,we have provided an up-to-date review of NRR catalysts mainly on theoretical works and highlighted the latest achievements on descriptors,which can be served as valid guidance of optimal catalysts.The descriptors are classified with adsorption energy and the corresponding derived ones,which can screen the NRR catalysts from various aspects.Finally,the challenges and opportunities in the descriptor field are presented.
文摘In today's fast-paced modern life, whether for fitness training, outdoor adventures, or daily commutes, we all yearn for quick-dry apparel that can rapidly wick away moisture and keep our bodies dry and comfortable. As a standout in functional textiles, quick-dry fabrics are becoming the top choice for more and more people, thanks to their exceptional moisture-wicking performance and rapid drying capabilities.
